Frangible rod and disk type safety valve



Aug. 21, 1934. Y

R. w. TRYON l-rrAL FRANGIBLE ROD AND DISK TYPE SAFETY VALVE I Filed Jan. 9. 1932 2. A cylindrical frangible element 7 is threaded weakened section 10. Below Patented Aug. 21, 1934 1,970,718 I FRANGIBLE non AND DISK TYPE SAFETY VALVE Richard W. Tryon and George M. Booth, Elizabeth, N. J., assignors to Standard Oil Development Company, a corporation oi Delaware Application January 9, 1932, Serial, No. 585,718 11 Claims. (01.22049) This invention relates to improvements in automatic release devices of the frangible type for containers which may be subjected to excessive pressure. The principal object of the invention is to provide a release device in which the frangible element is adapted to yield on direct tension. This is applied by pressure acting on a member of large cross-section area carried by the frangible element and adapted to be ruptured after the yielding of the frangible member. Other objects of the invention are to minimize the danger of corrosion, distortion and fatigue of metal, and the like, which may make release devices of the ordinary frangible disk type inoperative. The invention will be fully understood from the following description, read in' connection with the accompanying drawing in which:

Fig. l is a vertical section through a preferred form of the invention;

Fig. 2 is a transverse section on line 11-41 of Fig. 1 looking up;

Fig. 3 is a transverse section on line mof Fig. 1 looking down; I

Fig. i is a full elevation view of the frangible element of Fig. 1; and

Fig. 5 is a top view of Fig. i. V

in the drawing, reference numeral 1 denotes a dome shaped casting having an annular flange casting 3 has a corresponding 4. The flanges are secured tohas an enlarged in the center tune of the walls of the casting.

Within the casing 6 thus formed by the two castings, therev is provided a frangible element which is preferably in the form of a rod '1. The on both ends 8 and 9. The cut away at an intermediate portion to form a this section the frangible element '7 carries a circular flange 11.

h spider or platform 12 cast as part of the cast- 1 extends between the sloping walls of cast i l. The spider 12 is disposed in spaced relation to the enlarged portion of the casing 6. The spider 12 has a central threaded opening 12 adapted to support the frangible element 1 by means of the threaded end 9. The spider 12 has openings 14 so as to allow free flow of fluids.

A flexibly mounted frangible diaphragm or disk 15 has a central opening 16 which flts over the frangible element '7 below the flange ll. The

frangible element is indented or outer margin of diaphragm 15 is clamped between the flanges 2 and i so as to make a fluid-tight joint withthem. Backing plates 17 and 18 are provided one on each side of the diaphragm.

The portion of the frangible element '7 below 30 the flange 11 is inserted through the opening 16. A suitable gasket 19 is provided between the flange 11 and the upper backing plate 18. Nut 20 screwed on the end of the frangible element 7 supports the assembly of diaphragm 15, gasket 19 and backing plates 17 and 18, making a fluid-tight joint with them.

Casting 3 has an enlarged central cylindrical upper aperture defined by rim 21 and floor 22, joined by the right angular curvature of the walls of the casting. Spaced ridges or raised portions 23 of the floor 22 project radially a part of the distance towards the center of the casing e. Casting 3 has a smaller annular flange 2i on a narrowed portion. The flange is adapted to be secured to an outlet pipe 25 having a flange 26 by means of bolts 2'2.

Casting 1 has a smaller annular flange 28 on a narrowed portion. The flange is adapted to be secured to an inlet pipe 29 having a flange 30 by means of bolts 31.

The container on which the release device is to be used is connected with it through an inlet pipe 29, provided with a manually operable valve 29a opening into casing 6. Casing 6 is also connected with outlet pipe 25. Uutlct pipe 25 connected with casting 3 is provided with a lookbox or other suitable indicating device 30a.

The frangible element is preferably made of The extent to which the rod is weakened by cutting away at the section 10 is determined by the amount of pressure which the device is to withstand. It will be observed that the area of diaphragm 15 is very large compared with the cross -sectional area through section 10. Accordingly, pressure exerted on the upper face of the diaphragm has a multiplied effect on the frangible clement. Section 10 may, therefore, be made relatively thick and thereby resistant to failure through corrosion, but the section will nevertheless yield at the required pressure.

The diaphragm 15 is made of any ductile and flexible metal such as lead. The strength of this material should be suc as to amply sustain 105 the small shearing load imposed upon the exposed narrow annular area at the periphery of the backing plates, yet should be of such strength as to insure immediate failure in shear as soon as the tension rod failure allows the total load 1m upon the bac be transmitted didiaphragm at the periphery.

ing plates to as is practical. The operation can be obtained.

The operator will detect the failure of the other device by observing the look-box a, or

and the like. v

The foregoing description is illustrative only and various changes and alternative arrangeour copending transmitting I diaphragm for exertingtension longitudinally upon the rod, said diaphragin'being adapted to rupture when the rod breaks; and means whereby pressure is vented through'the' diaphragm.

2. A pressure release devlcje comprising a casing, a flexibly mounteqdlaphragln therein, a solid rod having a weakened section secured to the diaphragm, means'for ausing the diaphragm mounted so as tobe ruptured by the displacement of the diaphragm, means for venting pressure from the casing whenthe solid frangible No. 498,098 illedNovember 25, 7

an indicating device in the line so arranged as to show that pressure has been vented.

4. In a pressure release mounted for movement with the diaphragm.

6. A pressure release device, comprising a cas- 7. A pressure release device, comprising 2. cats-.- ing having an inlet for fluid under pressure, a flexible frangible diaphragm diaphragm when the rod and tured.

10. A pressure release device, comprising a casing having an inlet for fluid under pressure and Lemme ed on its opposite end by the casing on the inlet side of the diaphragm, the strength of the rod and diaphragm being so proportioned that the diaphragm is subjected to but a small fraction of the total existing fluid pressure until such time as the rod is ruptured, at which time the diaphragm is subjected to pressure of greater magnitude than that required to cause it to fail at the marginal portion and escape of the fluid is permitted through the outlet.

, RICHARD W. TRYON.

GEORGE M. BOOTH. 

